$\dfrac{12}{100} + \dfrac{5}{10} = {?}$
Answer: The fractions must have the same denominator before you can add them. Rewrite $\dfrac{5}{10}$ as $\dfrac{50}{100}$ $\dfrac{12}{100} + \dfrac{50}{100} = {?}$ $ = \dfrac{62}{100}$